The present invention relates to an interface of a telecommunications device and, more particularly, to an interface of a frame formatter of a baseband integrated circuit employable in a base unit and a hand unit of a digital cordless telephone.
In conventional cordless telephone systems, a basic communication device typically includes a base unit and a hand unit. The base unit typically has a direct wire link to a standard telecommunications network. The hand unit is mobile the base unit and has no wire link with the base unit. The base unit and hand unit communicate via radio frequency (RF), thus allowing for communications by the hand unit through the base unit with the standard telecommunications network.
Those skilled in the technology have sought to group more and more components on a single integrated circuit or "chip" for use in digital cordless telephones. Many benefits are possible through the grouping of components, such as, for example, smaller size, faster operation, and reduced noise interference. However, grouping of multiple components on a single chip is difficult to design, because suitable pathways for signal communications between the components are limited. The pathways are limited because of the time and space restrictions imposed by virtue of the physical constraints of the single chip.
Digital cordless telephones may exhibit various desired characteristics and advantages according to design of the protocol or "format" (sometimes herein, "frame format") of transmitted and received signals. A variety of formats, both between communications units and between components of those units, may be employed, and each impacts design choices. For example, when a particular, desirable format is communicated over radio frequency, communications units must appropriately operate to make communications possible through that format. Also, if varied applications are intended, the formats of the signal communications by the equipment may be preferable in certain designs as compared to other designs.
In conventional cordless telephone systems, the signals which pass between units and components of a system may include certain control sequences, or "channels", according to particular formats. These control sequences pass between pairs of units, typically a base unit and a hand unit, in both directions. The control sequences may include information such as voice data. The control sequences are dictated to some degree by the structure of the format. In addition to signals passing between pairs of cordless telephone units, signals must pass between various parts of a unit. Those signals passing between parts of a unit may or may not, depending upon the particular content and purpose of the signals, be the same as the signals communicated between unit pairs. Nonetheless, a wide variety of control sequences may be possible in most cases.
The various signals that pass between cordless telephone unit pairs and between the various parts of each of those pairs are necessary to control operations of the parts and units and to maintain communications of data and other information between units and parts. In order to communicate both data information, such as, for example, voice data, and also to control operations through communicated information, it is necessary that both control messages and desired data information pass between parts and units.